piano centered dynamics

[James E. Bailey]

I'm really tring here, there should be online classes to figure this out, it just doesn't make sense to me. If anyone would be willing to help, I've posted a sample of what the music looks like, and it can be seen here.

Really, all I would like is to have the dynamics centered between the two piano staves.

\version "2.11.47"

ChoirDynamics = {

s1\p

s4\< s2 s4\!

s1\f

s1*6

s1\f

s4\> s2 s4\!

s1\p

}

Words = \lyricmode {

ab4 bc cd de

\skip1

ij4 jk kl lm

mn no op pq

qr rs st tu 

uv vw wx xy 

yz ab bc cd

de ef fg gh

hi ij jk kl

lm mn no op

pq qr rs st

tu uv vw wx

}

SopranoMusic = \relative d'' {

\repeat unfold 4 {

d4 e g fis

\context Voice = SopranoOne { \voiceOne

r8 e gis a~ a fis d4

}

cis4 e fis g

}

}

SopranoWords = \lyricmode {

        ef4 fg gh hi

}

AltoMusic = \relative a' {

\repeat unfold 4 {

a4 a b ~b8 d~

\context Voice = AltoOne {\voiceTwo

d4 cis b a

}

g g b b

}

}

AltoWords = \lyricmode {

        ef fg gh hi

        vw wx xz za

        ef fg gh hi

}

TenorMusic = \relative d' {

\repeat unfold 4 {

d4 cis b d

\context Voice = TenorOne {\voiceOne

b d~ d8 e fis d

}

e4 d cis e

}

}

TenorWords = \lyricmode {

        ef fg gh hi

        vw wx xz za

        ef fg gh hi

}

BassMusic = \relative d {

\repeat unfold 4 {

d4 a' g d

\context Voice = BassOne {\voiceTwo

e fis a2

}

a4 a a, a

}

}

BassWords = \lyricmode {

        ef fg gh hi

        vw wx xz za

        ef fg gh hi

}

RH = \relative d'' {

        \repeat unfold 4 {

                <d a>4 <e a,> <<{g fis r8 e gis a~ a fis d4}\\{b4~ b8 d~ d4 cis b a}>>

                <cis g>4 <e g,> <fis b,> <g b,>

        }

}

pianodynamics = {

s1*9

s1\p

s4\< s2 s4\!

s1\f

}

LH = \relative d' {

\repeat unfold 4 {

<d d,>4 <cis a> <b g> <d d,>

<b e,> <d fis,> <d a> <fis a,>

<a, e'>4 <a d> <a cis> <a e'>

}

}

\score {

        <<

                \new ChoirStaff <<

                        \new Dynamics = dynamics \ChoirDynamics

                        \context Staff = women <<

                                \context Voice = "soprano" <<\voiceOne \SopranoMusic>>

                                \context Voice = "alto" <<\voiceTwo \AltoMusic>>

                        >>

                        \context Lyrics \Words

                        \context Staff = men <<\clef bass

                                \context Voice = "tenor" <<\voiceOne \TenorMusic>>

                                \context Voice = "bass" <<\voiceTwo \BassMusic>>

                        >>

                        \new Lyrics \with {alignAboveContext=women} \lyricsto SopranoOne \SopranoWords

                        \new Lyrics \with {alignBelowContext=women} \lyricsto AltoOne \AltoWords

                        \new Lyrics \with {alignAboveContext=men} \lyricsto TenorOne \TenorWords

                        \new Lyrics \with {alignBelowContext=men} \lyricsto BassOne \BassWords

                >>

                \new PianoStaff <<

                        \new Staff \RH

                        \new Dynamics = pianodynamics \pianodynamics

                        \new Staff <<\clef bass \LH>> 

                >>

        >>

        \layout {

                \context {

                        \type "Engraver_group"

                        \name Dynamics

                        \alias Voice

                        \consists "Output_property_engraver"

                        \override VerticalAxisGroup #'minimum-Y-extent = #'(-1 . 1)

                        \consists "Script_engraver"

                        \consists "Dynamic_engraver"

                        \consists "Text_engraver"

                        \override TextScript #'font-size = #2

                        \override TextScript #'font-shape = #'italic

                        \override DynamicText #'extra-offset = #'(0 . 2.5)

                        \override Hairpin #'extra-offset = #'(0 . 2.5)

                        \consists "Skip_event_swallow_translator"

                        \consists "Axis_group_engraver"

                }

                \context {\PianoStaff \accepts Dynamics}

                \context {\ChoirStaff \accepts Dynamics}

}

}